Calf weaning weight as a % of cow weight

[Hesstondriver]

We weighed the calves at weaning as usual and also weighed the cows at the same time . I’m just having a play with some numbers To work our calf weight as a % of cow weight and then benchmarking my cows having worked out a Dlwg.

how do I or should I adjust for cow BCS ? As this could massively skew the figures?

 

[shields kaiser]

As in % of cow weigh weaned for the same BCS, sorting everything for BCS 3 for example? Havent heard of this before

 

[Spartacus]

I havent done it but if I was I would just take the weight of the cow with no notice of condition score, if its putting its feed into itself more than the calf it isnt efficient surely? As it would take more feed than a smaller framed cow to hold its weight regardless of growing a calf to the same weight as a smaller framed cow.

 

[Farmer Fin]

The target is 50%. The main issue is the cows at the bottom as they are your inefficient ones who probably just get fat. Look at the top as well as these cows who lost a lot of condition may struggle to get back in calf and are not that desirable either.

 

[Old Spot]

Should aiming for 60% of dam at weaning

 

[Woolless]

@Samcowman should be able to help.

 

[Samcowman]

It’s quite good to get the calves weight as their 200 day weight so it evens out the early and late calvers. My computer program does this for me. Unless you want to give a bias towards earlier calvers and they are all weighed on the same day.
From memory I think 1 bcs is 50kg. But I think trying to adjust their weight for bcs is too technical for farm level data and would make it too complicated and does it matter what bcs the cow is as long as she gets in calf and is efficient??
You will however find the fatter/heavier calves are worse for efficiency.
I recorded this for a couple of years but haven’t for the last couple as the mobile scales were making things too slow and I had found out what I needed to with regards to cow weight and efficiency

 

[CiderJan]

I correct mine to 2.5 BCS. 1 condition score is 13% of live weight or about 80kg on 650kg cow. A 650kg cow at BCS 4 is 770kg.

There's pros and cons of both ways of looking at it but if a cow is fat at 4 BCS but stays at that level year on year then does it take any more feed?

I also like correcting BCS so I can compare weaning % by year because some years there's lots of grass and condition may increase across the herd and in others it is shorter and BCS is lower.

Ultimately it can get very complicated if you want it to, especially if you start looking at combined weight gain of cow and calves etc. That's where BLUP evaluations make sense such as with breedplan and creating EBVs.

 

[Kiwi Pete]

We weighed the calves at weaning as usual and also weighed the cows at the same time . I’m just having a play with some numbers To work our calf weight as a % of cow weight and then benchmarking my cows having worked out a Dlwg.

how do I or should I adjust for cow BCS ? As this could massively skew the figures?

Is there much variance across your herd?
Adjusting for BCS may have merit if there are heavy and light cows across your herd, if they are reasonably consistent then I would be more inclined to not bother.
Adjusting for calf age would be better use of your time, perhaps?
Again, if you calve a tight pattern then I wouldn't bother, other than to maybe take a bit off the oldest calves and put a similar adjustment onto the late ones.

200 days is a good one to work off, for us, because they are basically weaned and "the cow's job is done"

our best first-calver weighed 480kg and the calves were 726kg @200 days, our worst was 500kg with a 240kg calf, will be culled as she is a passenger

 

[Hesstondriver]

Is there much variance across your herd?
Adjusting for BCS may have merit if there are heavy and light cows across your herd, if they are reasonably consistent then I would be more inclined to not bother.
Adjusting for calf age would be better use of your time, perhaps?
Again, if you calve a tight pattern then I wouldn't bother, other than to maybe take a bit off the oldest calves and put a similar adjustment onto the late ones.

200 days is a good one to work off, for us, because they are basically weaned and "the cow's job is done"

our best first-calver weighed 480kg and the calves were 726kg @200 days, our worst was 500kg with a 240kg calf, will be culled as she is a passenger

I will adjust all weights to 200 days . I know birth weight so this is easy . To be fair most of my cows are pretty similar in bcs this year but some years they vary a lot depending on summer grass growth . I’ll have a play with the data and see what different methods give me .
If I put the time in to weighing the cattle I want to be using the info correctly and to allow me to make the correct decisions for breeding and culling .

 

[Kiwi Pete]

I will adjust all weights to 200 days . I know birth weight so this is easy . To be fair most of my cows are pretty similar in bcs this year but some years they vary a lot depending on summer grass growth . I’ll have a play with the data and see what different methods give me .
If I put the time in to weighing the cattle I want to be using the info correctly and to allow me to make the correct decisions for breeding and culling .

Good job you're all over it . All data is good data, I often think that maybe we adulterate it too much, "overthinking it" if we start adjusting for this and that.
Almost better just to put a note if a cow is a big butterball or light, than play with the numbers?

 

[Samcowman]

Culling out poor performing and oldest cows every year makes a big difference to overall performance. If you have time sort it by cow age as well to help your culling decisions. I set up a spreadsheet with a heap of formulas so all I had to do was put in cow weight, calf 200 day weight and cow age and it worked out the results for me.
I also don’t put the very biggest heifers to the bull any more after doing this because 800-900kg cows on average are the worst performers.

 

[Kiwi Pete]

Culling out poor performing and oldest cows every year makes a big difference to overall performance. If you have time sort it by cow age as well to help your culling decisions. I set up a spreadsheet with a heap of formulas so all I had to do was put in cow weight, calf 200 day weight and cow age and it worked out the results for me.
I also don’t put the very biggest heifers to the bull any more after doing this because 800-900kg cows on average are the worst performers.

Our smaller ones just seem to do everything better. The smallest heifer was standing for the bull 26 days after calving, and had a heifer calf 54% of her LWT at 200 days. Nearly everything I can measure has the same straight line downhill as your computer-screen above .

 

[shields kaiser]

I also don’t put the very biggest heifers to the bull any more after doing this because 800-900kg cows on average are the worst performers.

Hi Sam, you've provided some great info here, thanks. In relation to your above point, I am trying to stop the same problem before it happens and wonder do you have a "weight cut off" above a certain weight at say 13 months (as you know this will lead to heavier MW cows) or is it based on DLWG? For example DLWG to weaning? I suppose I'm asking when do you know when a heifer is going to fit your criteria - weaning or after a 1st winter?
Thanks!

 

[Samcowman]

Hi Sam, you've provided some great info here, thanks. In relation to your above point, I am trying to stop the same problem before it happens and wonder do you have a "weight cut off" above a certain weight at say 13 months (as you know this will lead to heavier MW cows) or is it based on DLWG? For example DLWG to weaning? I suppose I'm asking when do you know when a heifer is going to fit your criteria - weaning or after a 1st winter?
Thanks!

No worries.
I usually go through the heifers as a first draft at about 12 months old. This times in with when they have to be moved sheds due to calving cows. I will just draft the smallest third off at that point and the ones that are far outperforming the rest and ones from johnes families.
I will then have another draft a month later when we pelvic scan and give them their first vaccination. The ones cut out then are for temperament As such I don’t have a specific weight that they are too big just the biggest few which is usually about 1% so not many but worth doing.
Really though the best way to do it would be to have a terminal sire chosen on growth rate and a maternal sire on calving ease cow size and milking ability, this should ideally go along with type being wide muzzle and the maternal wedge shape.
This should be a way I will go in the future. With heifers, older cows and early calving first calvers to maternal and the rest to terminal. As a generalisation.

 

[scholland]

I would say it's absolutely essential to record bcs on cows at weaning as well as weight, that summer gained condition can go a long long way to keeping her fed over winter and it's cheap.

We don't adjust cow weight when dealing with weaning ratios, we just have the bcs in the next column, anything with a below average bcs and weaning ratio is for the chop.

Bcs a month pre calving, attitude, fertility and usual correctness things are also considered.

This year we had a wean ratio of 42% and average bcs of 3.9.
I'm reasonably pleased with that.

 

[Ministryman]

Is there much variance across your herd?
Adjusting for BCS may have merit if there are heavy and light cows across your herd, if they are reasonably consistent then I would be more inclined to not bother.
Adjusting for calf age would be better use of your time, perhaps?
Again, if you calve a tight pattern then I wouldn't bother, other than to maybe take a bit off the oldest calves and put a similar adjustment onto the late ones.

200 days is a good one to work off, for us, because they are basically weaned and "the cow's job is done"

our best first-calver weighed 480kg and the calves were 726kg @200 days, our worst was 500kg with a 240kg calf, will be culled as she is a passenger

Am I understanding your figures right? a 480Kg heifer weans either 1 calf at 726kg (3.4kg/day!) or 2(?) 313kg twins @200 days? and your worst was 48% of dam's weight?

 

[Kiwi Pete]

Am I understanding your figures right? a 480Kg heifer weans either 1 calf at 726kg (3.4kg/day!) or 2(?) 313kg twins @200 days? and your worst was 48% of dam's weight?

Yeah, she took on 3 calves

She's only allowed her one this year, as she was last to calve. Nice heifer.

Probably they would be bigger heifers if they didn't work hard from the start, I'd guess they might have hit 550kg if I calved them at 3 instead of 2, so the size "is there but hidden for a while"

Based on that guesstimate then, our worst heifer is much less efficient in terms of weaning %, more like 43% than 48%, it's window-dressing but it doesn't really hide the fact she looks after herself better than her calf - so she can go and we'll keep more replacements.

 

[Whitepeak]

This is probably a really stupid question, but I want to be sure. To adjust calf weights to 200 days is it just a case of multiplying the daily gain by 200 (liveweight minus birth weight, divide by age, multiply by 200).
Got new weigh bars this year, so I'm wanting to weigh everything once they come inside.

 

[Samcowman]

Pretty much but to get 200 day weight you would need to add back the birthweight.
My computer program does it for you though (SumIt). But if working off excel would be easy enough to set up a formula.